build up javascript to inject at the tail end of the page

StringBuilder stringBuilder = new StringBuilder();

stringBuilder.AppendLine("<script>");

//First wait until the SP.js is loaded, otherwise the notification doesn’t work

//gets an null reference exception

stringBuilder.AppendLine("ExecuteOrDelayUntilScriptLoaded(ShowNotification, \"sp.js\");");

stringBuilder.AppendLine("ExecuteOrDelayUntilScriptLoaded(ShowStatusNotification, \"sp.js\");");

stringBuilder.AppendLine("function ShowNotification()");

stringBuilder.AppendLine("{");

stringBuilder.AppendLine(string.Format("SP.UI.Notify.addNotification(\"{0}\");", "Save sucessful"));

stringBuilder.AppendLine("}");

stringBuilder.AppendLine("function ShowStatusNotification()");

stringBuilder.AppendLine("{");

stringBuilder.AppendLine(" var strStatusID = SP.UI.Status.addStatus(\"Information : \", \"<img src='/_Layouts/Images/STS_ListItem_43216.gif' align='absmiddle'> <font color='#AA0000'>Save successful.</font>\", true);");

stringBuilder.AppendLine("SP.UI.Status.setStatusPriColor(strStatusID, \"yellow\");");

stringBuilder.AppendLine("}");

stringBuilder.AppendLine("</script>");

//add to the page

Page.Controls.Add(new LiteralControl(stringBuilder.ToString()));